Tube bender



y 1944- J. 'N. ST. CLAIR TUBE BENDER Filed March 4, 1942 Q 4 INVENTOR.

John /V. 57f 670/7" 4T7 RNEY.

Patented May 23, 1944 UNITED STATES PATENT OFFICE TUBE BENDER John N. St. Clair, Kansas City, Mo. Application March 4, 1942, Serial No. 433,308

3 Claims.

This invention relates to hand operated tools of the character adapted for bending relatively small conduit, tubing or pipe of comparatively soft material, capable of being bent without preheating.

One of the important aims of this invention is to provide a tube bender of the aforementioned character, embodying means, for quickly and easily imparting an accurate and'uniform bend of predetermined degree to a pipe or conduit.

A further aim of the present invention is the provision of a bender having means incorporated therein for facilitating the positionin of a pipe between a forming anvil and a cooperating roller.

Another object of this invention is to provide a tube bender of rugged yet light construction, that can bereadily moved from one job to another; that is designed to accommodate tubing of various diameters; and that may be manually manipulated by exerting a minimum amount of force.

Other objects of the invention will appear during the course of the following specification, referring to the accompanying drawing wherein:

Fig. 1 is a side elevational view of a tube bender constructed in accordance with my invention, showing parts thereof and the tube being treated in two positions.

Fig. 2 is a top plan view of the tube bender.

Fig. 3 is a fragmentary elevational view of a portion of the side of the tube bender opposite to that shown in Fig. 1.

Fig. 4 is a front end elevational view of the tube bender; and

Fig. 5 is an enlarged fragmentary cross sec tional view of a portion of the bender taken along line V-V of Fig. 1.

Referring more in detail to the drawing, the numeral 6 designates an elongated base having downturned side flanges 8 mounted on U-shaped cross members ID for supporting the base in spaced relation above a floor or the like. Bolted or otherwise secured on base 6, as indicated at [2, is a bearing bracket I 4, having a head It provided with sockets I8, and 22 respectively.

Socket l8 screwthreadedly receives a stud 24 for pivotally carrying a forming anvil 26, which comprises a pair of arcuate segmental sections 28 and 30 respectively, joined by rivets or other securing means 32.

In cross section, members 28 and 30 when secured together, present a substantially semi-circular gIOOVe 34 to receive a tube, pipe or conduit 36. It will be observed from the drawing iii that section 30 comprises merely an arcuate rim portion while section 28, pivotally mounted on stud 24, is a complete segment.

It is important that the axis of arcuate face 1 34 of the anvil be offset'with relation to stud 24 so that in effect, the anvil 26 is eccentrically mounted on bearing bracket l4. Through such construction, rotation of anvil 26 about stud 24 in an anti-clockwise direction, as viewed in Fig. 1, will provide a wider clearance between the said anvil and base 6 to readily admit tube 36 from one side of the machine.

Means for locking anvil 25 in fixed relation to bracket I4 includes a latch pin 38 adapted to engag'e socket 22 inbearing head l6. Pin 38 is pivotally carried on a latch arm 43 intermediate the ends of the latter. One end of arm 46 is hinged as indicated at 42 to the. anvil while the other end of arm 40 is urged toward the bearing head l6 by spring 44 secured to said head.

.A stub shaft 46 screwthreaded or otherwise secured in socket 20 of bearing head l6, rotatably carries a lever 48 having an arm 50 provided with a laterally extending pin 52 upon which is mounted a forming roller 54 in substantially the same plane as anvil 26. Lever 48 is further provided with a reduced shank 56 for receiving one end of a pipe handle 58 of suitable length to facilitate bending of the tubular conduit 36 along the arcuate face of the anvil.

A calibrated stop or gauge 60 is adjustably secured to lever 48 by a set screw 62, and is adapted to strike the upper surface of the base 6, as indicated in dotted lines in Fig. 1, to limit the turning movement of the lever and thereby impart a predetermined degree of bend to the pipe.

A measuring bar 64 is slidably mounted in bearings 66 of the base 6 and is provided with a laterally projecting finger 68 for engaging one end of the pipe positioned between the forming anvil and roller ready for the bending operation. The measuring bar is retained in adjusted position by a clamping screw 10 and it is apparent that after setting said bar to the desired length at which the pipe is to be bent, any number of pipes or conduits may be bent to exact and uniform specifications.

As has heretofore been described, rotation of the forming anvil about axis 24 readily permits positioning of pipe 36 between the anvil and forming roller.

It is preferable however, to provide means for retaining the forming anvil in such pipe clearing position while the conduit is placed on the base prior to the bending operation, and for this purpose, a bevelled shoulder 12 is provided on the bearing member, as best shown in Figs. 1 and 2 of the drawing, for seating the inner end of latch pin 38. A slight pressure on the forming anvil in a clockwise direction (Fig. 1), causes the latching pin to move oif the bevelled seat and engage the socket 22, thereby firmly latching the anvil to the bearing head IS.

The operation of the machine is as follows:

The forming anvil is first rotated to pipe clear; ing position until its latch pin rests on the bevelled shoulder 12. then placed on the base between the anvil and forming roller and is moved to abutting engagement with the lateral finger of the measuring bar--this bar having been adjusted to expose duce the desired degree of bend in the tube, the lever is turned on its axis until the stop strikes the upper surface of the base. During this movement of the lever, the forming roller draws the tube against the arcuate face of the anvil, thereby producing a uniform bend therein. The lever is then returned to its forward position and, as will be observed, such movement is limited by the lower arm 50 of the lever, striking the proximal end of the base.

A tube bender has thus been provided that accomplishes all of the objects of this invention and while it is realized that machines having physical characteristics different from those shown in the drawing may be made without departing from the spirit of the invention, it is desired to be limited only by the scope of the appended claims.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. A tube bender of the character described, a base; a bearing bracket on the base; a forming The tube to be bent is 7 anvil carried by said bracket having an arcuate face; a lever pivotally mounted on the bracket having a forming member arranged to travel in a path complementary to said arcuate face when the lever is moved about its pivot to draw a tube against the arcuate face of said anvil; a stop adjustably fixed on the lever for limiting the turning movement thereof to predetermine the degree of bend of the pipe; and a measuring bar slidably carried by the base, said bar having a lateral projection for abutting engagement with an end of a straight tube when the same is positioned between the forming member and said anvil.

2. In a tube bender oi the character described,

anvil pivotally mounted on said bracket having t length required w t th gauge t t pro;-

"an arcuate face in eccentric relation to said pivotal mounting and cooperating with the base for holding a tube between said base and the arcuate face; means for latching the anvil to said bracket; and a lever pivotally mounted on the bracket having a forming member in the same plane with the arcuate face of the anvil and adapted to travel in an arcuate path when the lever is moved about its pivot to draw the tube against the arcuate face.

3. In a tube bender of the character described, a base; a bearing bracket on the base; a forming anvil pivotally mounted on said bracket having an arcuate face in eccentric relation to said pivotal mounting and cooperating with the base for holding a tube between said base and the arcuate face; a latch for releasably securing the 

